This invention relates generally to superimposing a character on video and in particular to superimposing a character on a video image displayed on a monitor in a video surveillance system. As used herein, character includes letters, numbers, symbols, and graphics.
Prior art systems have used text overlay and antialiasing methods to overlay text on video images from surveillance cameras. This overlaid text can provide various information such as date, time, camera being displayed and so forth. The quality of the video text provided has been limited by the standard window graphics packages available. These graphics packages only provide red, green and blue functionality for each pixel. To take advantage of the additional functionality of the underlying hardware, it has been necessary in the past to design a special window graphic package for the particular application thereby significantly increasing the complexity and cost of the final system. As a result, the prior art video surveillance systems have simply used the limited capability of the standard red, green and blue functionality of standard window graphics packages. This has resulted in overlaid text that has lacked the desired crisp, well-defined alphanumeric characters on the screen that are pleasing to the viewer's eyes.